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    <script>

        const obj = {
            b: 1
        }
        Object.defineProperty(obj, 'a', {
            value: '8',
            writable: false,
            configurable: true,
            enumerable: true

        })

        Object.defineProperty(obj, 'a', {
            value: '8',
            writable: false,
            configurable: false,
            enumerable: false

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        console.log('[ obj ] >', obj)
        console.log('[  ] >', Object.keys(obj))

        obj.a = 9


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